Can I NOT harcode domain name in IMG in Post?

I do a lot of <img> statements in my blog posts. I’m hardcoding the domain name each time, like:

img src=”https://www.googletutor.com/wp-content/images/something.gif&#8221;

I hate to think about all the changes I’d have to make if I ever changed my domain name. Is there some sort of code I can put in the page that signifies the site URL so I don’t have to hard code it?